2025 Theses Doctoral

Postural Control in Achilles Tendinopathy

Jezequel, Jonathan Ryan

Background:
Achilles tendinopathy (AT) is a common lower limb overuse pathology that results from excessive or insufficient mechanical loading. AT presents in 1.85 per 1000 of the adult population with up to a 27% recurrence rate. AT disrupts tissue morphology which alters mechanical load regulation and may also affect motor performance. The purpose of this study was to examine the relationship between AT morphology, motor performance, and function.

Methods:
APDM inertial sensors instrumented the modified Balance Error Scoring System (mBESS) and the modified Clinical Test of Sensory Interaction on Balance (CTSIB-M) to measure postural control. To manipulate AT strain, participants were tested unshod on a neutral sham orthosis, a 12 mm forefoot lift, and a 12 mm rearfoot lift. The Victorian Institute of Sport Assessment-Achilles and the Lower Extremity Functional Scale quantified function. A repeated measures ANOVA examined the interaction between variables.

Results:
Twenty-one participants (8 female, 13 male, mean age 35.5, SD 10.8 years) with AT were tested. mBESS postural control was different between involved and uninvolved limbs (p = .054), and between forefoot lift and rearfoot lift conditions (p = .053). CTSIB-M postural control was not different between participants with AT and control limbs (p = .534). Ankle range of motion was very strongly negatively correlated with postural control (p = .001).

Conclusion:
This study demonstrated a difference in unilateral postural control between involved and uninvolved limbs and between forefoot lift and rearfoot lift conditions. There was no difference in bilateral postural control between AT and control limbs.